Offshore wind energy

Authors: Ramakrishnan Thrissur Subramanian, Tran Quoc Ngu, March, 2025  

1      Description and History

The world’s first offshore wind turbine was installed at Norgersund, Sweden, in 1900 and the first commercial offshore windfarm was installed at Vindeby, Denmark, in 1991 with 11 Bonus 450 kW machines¹. The global cumulative capacity increased from ~8 GW in 2014 to ~75 GW by end of 2023. 10.8 GW of offshore wind capacity was added in 2023, 24% higher than the previous year, making 2023 the 2^nd highest year in terms of offshore wind installations ².

There are mainly two technical routes for type of offshore wind turbine generators: a) permanent magnet direct drive and b) permanent magnet semi-direct drive synchronous generator sets. The permanent magnet direct drive synchronous wind turbine system has the highest annual power generation, and the permanent magnet semi-direct drive synchronous wind turbine system has the lowest cost per kilowatt hour ³. The foundational structures of offshore wind turbines are more complex compared to onshore turbines mainly due to the harsh offshore environment where the turbines are subjected to greater wind loads, current loads and wave loads ⁴. Majority of the offshore wind farms are located on the continental shelf in water depths of about 10 m and 10 km off the coast ⁵. Offshore wind turbines must have strong support structures connected to the seabed by foundations and must be located above the crest level of the highest waves ⁶. Estimates show that the cost of offshore wind unit is double, or triple compared to an onshore wind unit depending on the site location ^5,7. 

Existing offshore wind turbines mostly consist of wind turbines installed with fixed foundations – gravity base, monopile, tripod and jacket in water depths less than 50m. The wind resource is substantial for water depths greater than 50 m and bottom-fixed offshore turbines are no longer attractive economically in these conditions ⁸. Following an initial concept proposed by William E Heronemus at University of Massachusetts in early 1970s, industrially funded research on floating wind turbines started in mid 1990s. Benefitting from advances in floating oil and gas platforms such as tension leg platforms (TLP’s), semi-submersibles and spars, floating offshore wind turbines with mooring systems and anchor foundations have been proposed and tested. In 2008, the first test floating wind turbine (TLP platform type) with a rated capacity of 80 kW was installed by Blue H Technologies off the Italian coast. Hywind with a capacity of 2.3 MW and a spar foundation installed by Statoil in the North Sea near Norway was the world’s first MW scale floating wind turbine. Principle Power Inc developed WindFloat with a semi-submersible foundation and 2 MW Vestas turbine.It was the second MW scale floating wind turbine and was installed offshore of Agucadoura, Portugal in water depth of 45 m ⁹. 

Asia and Europe had operational offshore wind capacity of 41 GW and 34 GW by the end of 2023 respectively. Outside Europe and Asia, North America had 42 MW of offshore wind in operation. Apart from wind turbines, offshore wind projects require critical balance of plant items such as large foundations to support the turbine and transfer the load from sea surface to the soil at depth, specialized vessels for wind turbine component transportation and installation, subsea cables to connect the turbines and transfer power, and ports specifically for assembly and storage ².

By the end of 2022, fixed-bottom foundations consisting of steel and concrete foundations dominate the offshore wind market with monopiles and jackets making up 70% and 17% of the total installations. Annually 3,880 units of fixed bottom foundations can be produced by 30 manufacturers globally. GWEC market intelligence predicts that more than 2,200 units are planned to be added globally by 2026 and there is enough capacity available to meet the demand growth from 1,679 units in 2023 to 3,430 units in 2030. Floating foundations are not expected to reach commercialization until the end of this decade with annual demand surpassing 200 units per year. Demand for cables is expected to grow by an average of 18% year-on-year from 2023 to 2030. Key trends driving the cable demand are shift from 33 kV to 66 kV for larger turbines, transition from AC to DC cables to reduce electrical losses in long distances and high-voltage direct current (HVDC) technology for power interconnection in cross border energy sharing. In 2022, only about 0.5% of global energy cable production facilities were capable of producing submarine cables ².

Vessels used for installation of offshore wind turbine and foundations (Wind Turbine Installation Vessels – WTIV) fall into two categories: heavy lift vessels (mostly for foundations) and jack-up vessels (majorly for wind turbines – including self-propelled vessels and barges without propulsion). The two major factors impacting the availability of the vessels are: Turbine MW size continue to grow beyond 12 MW – (approx. weight of nacelle is 500-800 tonnes, tower is over 2,000 tonnes and foundation weighs over 1000 tonnes) and hub height (ranges from 109 m to over 150 m). Ports provide support for component manufacturing, storage, wind site surveying, construction, operation and decommissioning. Ports are named according to the function they serve a) marine survey port, b) manufacturing port, c) marshalling (staging) port and d) operation and maintenance port. Before loading them on to WTIV’s, a dedicated laydown area, specialized equipment and quayside are required to lift and store the big components ².

Advancements in offshore wind technology include size and turbine design, innovations in foundations, strategies for grid integrations, subsea cable technology, floating wind turbines all of which were discussed above. Other important advancements are remote monitoring and maintenance to monitor turbine performance, detect faults, optimize maintenance schedules through predictive algorithms, reduce downtimes and operational costs. Integration of digitalization and data analytics optimizes wind farm operations, improve energy forecasting and enhances overall project efficiency and performance. Using advanced modelling and simulation tools, optimization of wind farm layout facilitates to maximize energy yield, reduce wake effects and mitigate environmental impacts ¹⁰. 

Offshore wind turbines have grown substantially in size and power rating over the past decade with growth in average installed turbine rating from 7.7 MW in 2022 to 9.7 MW in 2023. To allow the supply chain and R&D investments to be paid off and allow the benefits of standardization, industrialization and industry learning to lower costs some of the original equipment manufacturers (OEM) have expressed hesitation to continue increasing the turbine size ¹¹. In 2023, Chinese OEM Goldwind installed 16 MW offshore wind turbine (GWH252-16MW) with 123 m long blades and rotor diameter of 252 m and swept area of 50,000 sq.m. Mingyang commissioned  (MySE 16-260) overtaking Goldwind with a rotor diameter of 260 m and swept area of 53,902 sq.m. Mingyang also unveiled MySE 18.X-20MW with rotor diameter ranging between 260-292 m and equipped with anti-typhoon technology capable of withstanding category 17 typhoons (56.1 to 61.2 m/s). Mingyang also unveiled plans to develop MySE 22MW with rotor diameter over 310 m and suitable for both fixed-bottom and floating applications. General Electric (GE) unveiled plans to develop next generation its Halide-X variant that has a capacity between 17-18 MW. Vestas’s new wind turbine V236-15MW has a rotor diameter of 236 m and swept area greater than 43,000 sq.m¹².

GWEC estimates that more than 410 GW of new offshore wind capacity is expected to be added over the decade (2024-2033). There is still an implementation gap between the rate of annual installations and declared targets ². Some of the major challenges include: a) Technical challenges like complex seabed conditions, harsh marine environment and logistical complexities of construction and maintenance b) Impact on marine ecosystems, coastal communities and wildlife habitats c) Regulatory frameworks leading to legal and administrative bottlenecks causing project approval delays and uncertainties for developers d) Careful consideration and management is required to handle socio-economic implications including local community engagement, job creation and equitable distribution of benefits e) Technical challenges related to grid stability, reliability and capacity constraints ¹⁰. 2023 was challenging for offshore wind industry with increased capital costs, interest rates and high inflation. The cost of capital increases due to accounting all the risks related to grid, land, legal, procurement, off-taker, forex rates and political. By addressing these key challenges related to political/legal, social, technological, economic and ecological performance, the implementation gap can be reduced and will facilitate in achieving the offshore wind energy capacity targets set by governments ².

2      Economic Performance

Economic performance of onshore wind power plants or other renewable technologies can be measured in different ways and each metric will bring their own insights. To facilitate the comparison of costs by country or region for the same technologies, identification of key drivers is essential ¹³. The major key assumptions are as follows ^13,14:

• Net Facility Output (in MW)
• Total Capital Cost – equipment cost (factory gate, free onboard [FOB] and delivery at site), project installation cost including fixed financing costs (in $/kW or $/MW)
• Operation & Maintenance (O&M) Costs – Fixed (in $/kW-year) and Variable ($/MWh)
• Capacity factor of the project
• Construction timeline (in months) and Facility life (in years)
• Levelized Cost of Energy (LCOE – in $/MWh)

LCOE is broadly defined as function of the total lifecycle costs relative to the amount of energy produced ¹³:

LCOE = average lifetime levelized cost of electricity generation, l_t = Investment expenditures in the year ‘t’, M_t = O&M expenditures in the year ‘t’, F_t = Fuel expenditures in the year ‘t’, E_t = Electricity generation in the year ‘t’, r = discount rate and n = life of the system.

Weighted average cost of capital (WACC) is used as the effective discount rate and it implies a weighting of the costs of different financing resources ¹⁵. The WACC ranges between 5% to 10% with OECD (Organization for Economic Co-operation and Development) countries and China having WACC between 5% and 7.5% due to relatively low and stable regulatory and economic policies which reduces the perceived risk of renewable energy projects ¹³.

Direct Costs^* – Preventive, Corrective and Proactive Maintenance, Indirect Costs^** – Port, Vessels, Labour etc. DECOM – Decommissioning costs are also financed up front as part of the CAPEX- capital expenditure but appears at the end of life in the overall timeline ¹⁵.

Energy Transition Investment Trends 2024 report released by Bloomberg New Energy Finance (BNEF) noted that $1.77 trillion was invested in energy transition with major portion being invested in renewables and grids (almost $1 trillion). BNEF states that an investment of about $12 trillion would be required in the power systems till 2030 (average of $2 trillion per year) to meet the Conference of the Parties 28 – COP28 – Global Renewables and Energy Efficiency Pledge of tripling renewable energy from 2022 levels by 2030 and meet Paris accord’s 1.5⁰C target and net zero commitments of many countries and companies ¹⁶. To achieve the above targets, the International Renewable Energy Agency (IRENA) has recommended at least 2 TW of wind power by 2030 and 8 TW by 2050 ¹⁷.

Projections according to IRENA’s World Energy Transitions Outlook estimate that global offshore wind installations must reach 380 GW by 2030 and 2,000 GW by 2050 to deliver one third of required global power sector emission reductions for a net zero world by 2050. The world bank through its Energy Sector Management Assistance Program (ESMAP) has estimated a technically extractable offshore wind potential of 71,000 GW globally. 70% of this potential is distributed across 115 countries which are outside the traditional markets of Europe and China, indicating significant investment opportunities for offshore wind energy in new and emerging markets ^17,18.

Global Wind Energy Council (GWEC) in their Global Offshore Wind Report 2024 offer a framework to accelerate the growth of offshore wind, across seven key vectors ²:

• Accelerating the financing of offshore wind in mature and emerging markets, across global north and south.
• Growing demand for offshore wind – industrial off-takers and development of green products to accelerate growth.
• Building the global offshore wind supply chain for a 1.5⁰C world.
• Accelerating permitting for offshore wind.
• Collaborating with communities and driving social consensus.
• Realizing a trained and diverse workforce.
• Building modern and efficient grids to underpin the energy transition. 

10.8 GW of new offshore wind was operational globally in 2023, bringing the total global offshore capacity to 75.2 GW by end of 2023. Out of the 10.8 GW, China added 6.3 GW and Europe added 3.8 GW accounting nearly 94% of the total installed capacity globally. 2023 was also a turbulent year for offshore wind with major challenges such as inflation, increased capital costs and supply chain constraints due to which GWEC market intelligence downgraded its global offshore wind outlook by 10% for capacity additions in 2024-2028 compared to the 2023 projections ². 

The following table provides a comparison of LCOE of Offshore Wind with other renewable energy technologies ¹³:

Based on Lazard’s LCOE analysis report 2024, the LCOE of conventional power plants are as follows ¹⁴: 

• Gas Peaking – 0.110 $/ kWh to 0.228 $/ kWh
• US Nuclear – 0.142 $/ kWh to 0.222 $/ kWh
• Coal – 0.069 $/ kWh to 0.168 $/ kWh
• Gas Combined Cycle – 0.045 $/ kWh to 0.108 $/ kWh

The Global Weighted Average Capacity Factors in 2023 for renewable technologies are as follows ¹³: Solar PV – 16% (up from 14% in 2010), Concentrated Solar Power (CSP) – 55% (up from 30% in 2010), Onshore Wind – 36% (up from 27% in 2010), Offshore Wind – 41% (up from 38% in 2010), Hydropower – 53% (up from 44% in 2010), Bioenergy – 72% (no change from 2010) and Geothermal – 82% (down from 87% in 2010). Technological advancements in floating offshore wind have enabled the sector to expand beyond the shallow depth waters, but the costs remain significantly higher than fixed bottom installations. Overall project development costs remain relatively high due to complex infrastructure requirements. The operational efficiency is also improved by specialized installation and maintenance vessels ¹³. Offshore winds are 20% stronger than onshore and provides higher capacity factor of 41%. The projects can be installed on very large scale and avoids competition for land with agriculture, urban development, conservation areas etc. Despite the 63% cost reduction in LCOE from 2010 to 2023, the construction costs are approx. 3 times of onshore wind and O&M costs are 1.5 times ³. Despite these major challenges, offshore wind remains an attractive and long-term investment opportunity for developers and investment firms. By solving the bottlenecks related to supply chain, advocating for transparent auctions and seabed lease designs, stable regulatory frameworks, efficient permitting procedures, grid constraints etc. offshore wind can play a vital role in decarbonization ².

3      Ecological Performance

Offshore wind energy has huge prospects to prevent greenhouse gas (GHG) emissions as well as other airborne pollutants through substituting for fossil fuel-driven electricity generation. As compared to fossil fuels, wind energy emits zero direct GHG, requires no fuel mining/drilling, utilizes minimal amounts of water, making it amongst the cleanest form of energy production ^19,20. Offshore wind produces only 8–35 grams of CO₂ or its equivalent (CO₂eq) per kilowatt hour (kWh) of electricity generated (gCO2eq/kWh), far below coal (740–910 g CO₂eq/kWh), natural gas (410–650 g CO₂eq/kWh), and even rooftop solar (26–60 g CO₂eq/kWh) ^21,22. The low-carbon footprint of offshore wind highlights its absolute significance in power sector decarbonization and climate target achievement. Global Wind Energy Council GWEC indicate that 494 GW of offshore wind can be installed globally by 2030 as part of the path to limiting global warming to 1.5°C ²³.

While Offshore Wind Energy OWE development is an effective way to reduce energy-related greenhouse gas (GHG) emissions, it will incur environmental impacts related to the manufacturing, installation, operation and maintenance(O&M), and decommissioning and end-of-life (EoL) recycling of wind turbines, foundations, and transmission equipment. These impacts remain largely uncertainwith the turbine size, the distance from shore both increasing, as well as with recent changes in component technology development ²⁴. But most of these emissions only need to happen once for each wind turbine, which will be in service for at least 25 years. In this time, they will be producing electricity without emitting any more carbon dioxide, except for those from the vessels used for service and maintenance. These account for about 10% of total emissions from offshore wind ²⁵. It has been found that 78.4% of life cycle emissions are due to component manufacture and installation, 20.4% are the result of operation and maintenance, and only 1.2% are associated with decommissioning ²⁶. Most of these emissions are a result of the high quantity of materials such as steel and concrete used, especially in monopile and jacket foundations. Steel, which constitutes 71–79% of turbine mass, has a high embodied carbon footprint, and concrete used in foundations is also a major contributor to global CO₂ emissions from cement production ^27-29. Remaining materials like fiberglass, carbon fiber, and resins, which are used in turbine blades, represent specialized environmental challenges due to their complex composite structures that are difficult and costly to recycle ³⁰.

Although approximately 85–90% of a wind turbine’s material is theoretically recyclable, actual recycling rates—particularly of blades—are low because of economic, technical, and regulatory challenges ^28,30. Blades, typically glass fiber-reinforced plastics (GFRP), are among the most challenging components to recycle and require energy-intensive processes that produce hazardous dust. Yet, recycling turbine components can reduce lifecycle emissions significantly, with studies showing that recycling can save at least 35% of carbon emissions per kWh compared to manufacturing components from raw materials ³⁰. Yet, due to a lack of good recycling infrastructure and circular economy policy, much of this material is currently ending up in landfill.

Offshore wind carbon footprint has been reduced over the years due to technology innovation and the deployment of larger, more efficient turbines. Offshore wind farms being built today put up turbines of 10–15 MW, reducing emissions per unit of energy produced ^23,31. Moreover, innovations in materials—i.e., lighter carbon fiber and improved alloys—and more efficient transport and installation processes have contributed to lowering lifecycle emissions ^29,30. Early circular economy and recyclability design strategies are increasingly integrated into new offshore wind developments, yet there are significant gaps in regulatory policies and industry practices to embrace circular approaches in full ^20,28,30.

Nevertheless, there remain some challenges. Blade represents the most pressing challenge as these are usually made from GFRP which is a complex material and difficult to treat due to high costs, energy use and safety risks. The huge volume of steel for foundation – around 3.5 million tonnes globally, which can only grow as there is more deployment offshore. Also, wind turbines nowadays are made up mostly of steel and concrete, which both contain a high embodied carbon that needs to be reduced through innovation in material and process^27-29. Transport and installation, particularly for offshore wind farms at great distances from the shoreline, also add to the lifecycle emissions since heavy-duty equipment and vessels are necessary ^26,32.

Offshore wind energy is quickly emerging as a crucial solution to climate change through the utilization of renewable power and the reduction of greenhouse gas emissions. Although it offers vast environmental benefits, its ecological effects on marine ecosystems, biodiversity, and fisheries are also the targets of detailed research and controversy. The understanding of these interactions is crucial in order to ensure the sustainable development of offshore wind farms (OWFs)^23,33.

The impact of OWFs on birds, particularly seabirds, remains a problem. Initial wind farms caused collision risks to birds due to poorly planned site selection. Modern wind farms are designed to reduce such risks. However, migratory seabirds and bats may still be subjected to habitat disturbance and migratory route alteration. Wind farm noise pollution and vibrations also impact marine mammals differently, potentially interfering with their communication and navigation abilities. However, the impacts are relatively less significant in character compared to other human endeavors like fossil fuel extraction ^23,34-37.

Bases of offshore wind turbines act like artificial reefs to enhance marine biodiversity by providing surface areas for organisms such as amphipods, anemones, and mussels to benthically colonize. Reef effect attracts upper trophic level species including fish, crustaceans, and even mammals, as structures offer food sources, shelter, and breeding. Such enrichment in biodiversity can induce cascading influence on ecosystem functions. But these man-made reefs also may provide harborage for non-native species, which would eliminate native habitats and ecosystems^38-40.

OWFs bring about complex relationships with fisheries. While the exclusion effect of fisheries in wind farm areas prevents some practices like bottom trawling, it might enhance marine diversity by serving as ‘de facto’ no-take areas. This can lead to increased fish stock densities and larger sizes of commercially significant species such as lobsters and cod. Displaced fishing effort, however, could impose additional pressures on other ecosystems, and alterations to sensory environments (e.g., noise and electromagnetic fields) may impact fish behavior, migration, and breeding. Passive fishing methods, such as pot fishing, can utilize increased crustacean densities in OWFs ^38,39,41,42.

Installation and operation of OWFs generate underwater noise and Electromagnetic Fields EMF, which affect marine life. Impulsive piling sounds during installation may disturb fish, seabirds, and marine mammals, while continuous operating noise potentially disrupts communication and predator-prey interactions. Submarine cables that generate negative EMFs may disrupt the orientation and mobility of EMF-sensitive organisms like elasmobranchs. Even though these effects are documented, their long-term ecological implications are unknown ^43-45.

The presence of turbine foundations and support facilities alters local hydrodynamics, influencing water flow, sediment transport, and vertical mixing. These changes have direct effects on benthic habitats and larval dispersal, which consequently have potential impacts on primary and secondary production. These changes may benefit certain species but can also impact dominant ecological balances, depending on the local condition and character of the ecosystem ^46,47.

The environmental effects of OWFs vary throughout the whole lifecycle from installation to dismantling. With installation, seabed disruption and sediment transport are able to reversibly alter biodiversity and ecosystem functioning. Operationally, however, phases increase biodiversity through artificial reef effects, providing surfaces for settlement and food subsidies. Dismantling brings additional challenges in the form of removal of resident artificial habitats where structures are dismantled. Partial decommissioning, such as failing to strip scour protection layers, is becoming more prevalent in order to minimize ecological disturbance ^43,47-49. 

OWFs influence various trophic levels within the marine ecosystem. Introduction of hard substrates adds support to benthic fauna and primary producers, leading to higher biodiversity with an associated increased attractiveness to apex predators like seabirds, fish, and marine mammals. The enrichment at the trophic level indicates the need for environmental management policy that balances renewable energy development and conservation. OWFs also impact carbon sequestration and nutrient cycling services of the ecosystem and therefore influence big-picture ecological processes ^40,42,50,51.

The fast-paced development of offshore wind energy necessitates intense scientific exploration of their combined environmental impacts. Elaborate methodologies such as ecosystem modeling and long-term monitoring are needed to understand trophic interactions, migration, and species adaptation. Policymakers and developers must incorporate adaptive management practices so that OWFs will serve both renewable energy needs and marine conservation. Collaborative approaches, like multi-purpose marine spaces and coexistence with aquaculture, can achieve the highest possible ecological and economic benefit of offshore wind energy ^51-53.

4      Social Impact

Offshore wind power is a key component of the transition to renewable energy with important environmental and economic benefits. However, the use of the technology also raises essential social questions. On public acceptance, right up to equity and quality of life, the social impact of the technology must be effectively managed in order to benefit its long-term success.

Surveys have time and again shown that wind power enjoys widespread public support, mainly due to its ability to reduce greenhouse gas emissions and combat climate change. Converting such acceptance into local acceptance can be a challenge, nonetheless. Public opposition usually arises due to concerns related to visual impacts, noise, and disruption of traditional land uses or marine ecosystems. For example, the visual prominence of wind turbines over seascape and landscape, and their unavoidable visibility, have been a source of debate for a long time. People also worry about noise pollution and shadow flicker, but regulatory tools, such as setbacks, can help avoid these impacts ^21,54-56.

Surprisingly, attitudes towards offshore wind developments may change. For instance, public opinion polls of developments like the U.S. Block Island Offshore Wind Project showed that while people were initially worried, attitudes soon became milder or even positive, once the development was complete and the residents understood the true impacts. Such a change in attitude is quite often influenced by participatory action and procedural justice, as, if the planners feel involved and heard, there is a tendency for the projects to be embraced by the residents ^57,58.

Offshore wind farms have numerous positive impacts on host regions, one of the most significant ones being significant job opportunities in various lifecycle phases. Installation, construction, and operation of offshore wind farms require professional laborers, promoting the development of employees along coastal areas. For example, it is predicted that the world’s offshore wind workforce will grow by 50% from 2024 to 2028, creating tens of thousands of new jobs. These positions cut across various industries, ranging from technology development, operations, and maintenance. Offshore wind capacity expansion in Europe alone could add over €200 billion to the economy by 2030 ^23,59,60.

Community benefit schemes are another way in which wind energy benefits society. They typically cover the provision of money for local infrastructure, skills development schemes, and community ownership schemes that offer a financial return to communities. These kinds of projects are vital in easing social disparities, particularly in underprivileged or peripheral areas. Offshore wind also serves to slow down health risks introduced by pollution caused by fossil fuels, thus fewer respiratory problems and other diseases among nearby populations^58,59,61.

Despite its benefits, offshore wind development can be plagued with issues. Visual impacts are still the most severe issue for residents near coastal lines. Large turbines disrupt normal landscapes and seascapes and lead to aesthetic discontent. While visual irritation typically decreases with greater distance from turbines, nearness can lead to issues such as shadow flicker and felt intrusions upon natural beauty. Noise from the construction and operation of turbines, including low-frequency noise, has been linked with disturbance of sleep and general annoyance. Although there are no known direct health effects, these factors can affect the quality of life of the residents^54,56,58.

Offshore wind farms also affect economic activities, particularly fishing. Fisheries are likely to suffer from spatial competition because wind farms occupy traditional fishing grounds, leading to reduced access and potential economic loss for fishing communities. Even when artificial reefs created by turbines enable higher aggregation of fish, much of the fishing community grumble that this compensates for none of the historic livelihood loss. Additionally, efforts to resettle fishermen into alternative vocations, e.g., maintenance labor or environmental monitoring for windfarms, have encountered opposition on grounds of skill mismatching^39,62.

Distributional equity is another problem of concern. The communities that are most affected by offshore wind farms are not necessarily the communities that gain the most benefits. Some coastal communities, for example, may feel increased housing pressure and infrastructure burden at construction phases, while economic gains are often harvested at corporate or national levels. This discrepancy highlights the need for fair compensation mechanisms and pre-consultation, participatory approaches with affected communities to answer questions of environmental justice^55,59.

To offset such social impacts, robust strategies of benefit-sharing and community consultation are required. Engaging the local stakeholders at an early and sustained level can potentially foster trust and a “social license to operate.” Practices like Local Community Liaison Officers being appointed, conducting participatory workshops, and designing benefit programs tailored to local needs are becoming prevalent among developers. They encompass Denmark’s co-ownership models, where communities acquire interests in wind farms, and Community Benefit Agreements (CBAs) funding community infrastructure and social initiatives^57,59.

Moreover, the integration of socioeconomic considerations into planning processes through methods like Strategic Environmental Assessments (SEAs) and Maritime Spatial Planning (MSP) can help anticipate and prevent conflicts. Governments and developers must collaborate to reconcile the interests of different stakeholders, including fishermen, locals, and renewable energy advocates^55,62.

Offshore wind power social impacts are two-way, having positive opportunities along with challenges. Offshore wind farms contribute towards economic growth, job creation, and public well-being while creating aesthetic problems, fairness issues, and effects on public welfare. Offshore wind power, through tackling these issues from the very beginning by adopting transparent planning, fair compensation, and community engagement, can expand on as part of sustainable growth^{21,23,58,59,61}.

5      Political and Legal Aspects

Offshore wind is key to meeting global climate goals and fundamental step to enable the successful deployment globally is the permitting process. Currently there are three models: centralized – governments take control of the process and decreases risk for developers, decentralized – two stage model that gives developers greater flexibility but also higher risk, hybrid – combination of other two and is easier to adapt to particular country contexts based on the respective political, fiscal and cultural backdrop. The deployment models are inclusive of the permitting process like conducting of marine spatial planning (MSP), environmental and social impact assessment (ESIA), stakeholder management and gaining requisite approvals during the project development cycle ⁶³.

The key recommendations based on the policy brief by IRENA and GWEC under the Collaborative Framework for Ocean Energy Technologies and Offshore Renewables are ⁶³:

• One stop shop – Establish capable institutions for efficient permitting
• Stakeholder Consultations – Engage local communities throughout the project
• Mandated Lead Times – Set limits to reduce bureaucracy and disputes
• Digital Training Courses – Train staff to use digital tools for permitting
• Digital and Searchable Databases – Develop database for streamlined processes
• Alignment of Land and Ocean Use – Clear guidelines for offshore infrastructure
• Emergency Clearing Mechanisms – Fast track legal systems for dispute resolution
• Energy Infrastructure Permits – Standardize regulations for deployment

The 1982 UN Convention on the Law of the Sea (UNCLOS) provides the primary international legal framework for offshore renewable project development, jurisdiction in different maritime zones and addressing sovereignty. Subject only to the right of innocent passage for other states’ ships, coastal states have exclusive sovereignty to install offshore renewables (0-12) nautical miles. Exclusive Economic Zones (EEZ) up to 200 nautical miles, coastal states have sovereign rights to produce energy from winds, currents and water but balance these with overflight, submarine cables/pipelines, freedoms of navigation for other states. Similar sovereign rights apply to continental shelf with limits respecting high seas freedoms, high seas are currently not feasible for offshore installations due to technical and economic constraints. Coastal states are also mandated by the UNCLOS to protect and preserve the marine environment including mitigation of offshore installations like underwater noise, biodiversity risks and habitat loss⁶⁴.

To accelerate the deployment of offshore renewables, there is a need for stable, streamlined and binding regulatory frameworks that will strongly address the lengthy and complex authorization procedures. Many states have shifted from first come, first served to competitive auctions for site allocations. This ensures efficiency and also increases the investors’ confidence. Some countries have one stop shop systems using centralized authorities to streamline licensing and reduce administrative burden and delays. In order to avoid overlap and delays there is a need for coordination between dedicated legislation and agencies and clearly defined timeframes ⁶⁵. An example of the permitting process in established offshore wind market is as follows ⁶⁶:

• Tendering: Maritime Spatial Planning (MSP) for Site Development Plan (SDP)  Site investigation of the areas defined in the SDP  Areas are auctioned in a competitive procedure  The bidder who has been awarded a contract can erect wind turbines on the investigated site.
• Open-door Procedure: Developer submits an application for Planning Permission  Competent authorities and public interest bodies consultation  Developer revises its proposal  The application documents are open to public inspection  Applicants have an opportunity to present their projects  Developer prepares Environmental Impact Assessment (EIA) and Risk Analysis  Standard Investigation Concept  Grant of planning permission based on submitted documents.

For new and emerging markets, guidelines and good practices in environmental licensing for development of offshore projects are as follows ⁶⁶:

• Establishment of a national offshore wind energy production target
• Mapping of marine offshore wind zones
• Adoption of “one-stop-shop” procedure
• Maritime land concession regimes: Open-doors and Tenders
• Standard procedure guide in environmental licensing for offshore wind farms
• Development of Environmental Studies
• Public, authorities and stakeholders’ consultation
• Supply Chain Development Statement

Key points on subsidies, incentives and other related mechanisms globally are summarized as follows ⁶⁷:

• System of green certificates and guarantees of origin issued for produced renewable energy and can be sold at minimum guaranteed price to the network operator or on the market at a higher price. 
• To support grid connections, a cable subsidy has been provided for existing domain concessions. To ensure grid connection certainty, new installations will connect to Modular Offshore Grid (MOG-II) with compensation mechanisms. 
• Offering long term contracts (up to 30 years) for offshore wind projects, ensuring stable revenue through feed-in tariffs, thus boosting investor confidence by making it a predictable business environment. 
• Tax incentives like exemption from federal taxes, tax on imported equipment and components for turbines, higher investment and production tax credit with potential for more benefits when using more domestic content and installation of the project in energy community locations. 
• To avail some of the benefits, the projects must also meet the labor standards, support local economies and job creation. 
• Governments clearly indicating a long-term capacity target for offshore wind power which will demonstrate a strong political commitment and will attract investments. Regulatory uncertainties can be reduced by providing a strong legal framework for grid connectivity and leasing. 

International bodies like IRENA ⁶³, IEA Wind Technology Collaboration Programme (TCP) ⁶⁸ and Paris Agreement adopted in 2015 under United Nations Framework Convention on Climate Change (UNFCCC) ⁶⁹drive global offshore wind policies by setting targets and encouraging legal frameworks for climate goals. North Seas Energy Cooperation (NSEC) 260 GW offshore wind target by 2050 promotes cross-border collaborations, reduce political barriers, enhanced grid integration and permitting harmonization⁷⁰. A diplomatic and multi-stakeholder initiative founded by GWEC, IRENA and Government of Denmark at COP 27 called Membership of the Global Wind Alliance (GOWA) has been joined by 20 governments and have pledge to collaborate towards installing 380 GW of offshore wind by 2030 and 2000 GW by 2050 ². 

International communities and global industry have welcomed the offshore wind targets set by the governments in COP 26 and COP 27 and to push it to the forefront of many countries’ renewable development. To unlock the offshore wind potential and reach the set targets, the development of cohesive, efficient and accelerated permitting protocols and alleviate the main factors hampering the permitting like complexity of administration and bureaucratic processes, lack of central authorities, lack of holistic planning to capture complex stakeholder interactions, streamlined digital resources and clear shared understanding of permitting rules between promoters and permitting entities ⁶³. Technological innovations are a critical factor for global energy transition and will enable in reduction of cost of energy and large-scale offshore wind deployment. Reports published by GWEC and BCG suggest that by 2026/27 all the regions except China will face severe supply chain bottlenecks in offshore wind components and a global collaboration between industry and government is more important than ever ².

References

1          University of Strathclyde, G. Offshore Wind Turbines.  

2          Global Wind Energy, C., Rebecca, W. & Feng, Z. Global Offshore Wind Report 2024. 156 (Brussels, Belgium, 2024).

3          Su, X. et al. Offshore Wind Power: Progress of the Edge Tool, Which Can Promote Sustainable Energy Development. Sustainability 16, 7810 (2024). https://doi.org:10.3390/su16177810

4          Wu, X. et al. Foundations of offshore wind turbines: A review. Renewable and Sustainable Energy Reviews 104, 379-393 (2019). https://doi.org:10.1016/j.rser.2019.01.012

5          Esteban, M. D., Diez, J. J., López, J. S. & Negro, V. Why offshore wind energy? Renewable Energy 36, 444-450 (2011). https://doi.org:10.1016/j.renene.2010.07.009

6          Angus, M., Eric, U., Ulf, M., Christine, G. & Virginia, S.-O. B. Global trends in renewable energy investment 2013. (Frankfurt School-UNEP Centre/BNEF (2013)).

7          Wu, J., Wang, Z.-X. & Wang, G.-Q. The key technologies and development of offshore wind farm in China. Renewable and Sustainable Energy Reviews 34, 453-462 (2014). https://doi.org:10.1016/j.rser.2014.03.023

8          O’Kelly, B. C. & Arshad, M. in Offshore Wind Farms     589-610 (Elsevier, 2016).

9          Laura, C.-S. & Vicente, D.-C. Floating offshore wind farms.  (Springer International Publishing, 2016).

10        Dr. Rohit Kumar, G. Advancements in Offshore Wind Energy Technology: Challenges and Opportunities for Sustainable Power Generation. Indian Journal of Renewable Energy 1, 1-6 (2024). 

11        Angel, M. et al. Offshore Wind Market Report: 2024 Edition. (National Renewable Energy Laboratory).

12        Adrijana, B.     (2024).

13        International Renewable Energy, A. Renewable Power Generation Costs in 2023. 211 (Abu Dhabi, 2024).

14        Lazard & Roland, B. Lazard’s Levelized Cost of Energy Analysis – June 2024. 48 (Lazard, 2024).

15        Bosch, J., Staffell, I. & Hawkes, A. D. Global levelised cost of electricity from offshore wind. Energy 189, 116357 (2019). https://doi.org:10.1016/j.energy.2019.116357

16        Bloomberg New Energy, F. Energy Transition Investment Trends 2025. (2025).

17        International Renewable Energy, A. Tracking COP28 Outcomes: Tripling renewable power capacity by 2030. 20 (Abu Dhabi, 2024).

18        The World Bank – Energy Sector Management Assistance, P. Offshore Wind Technical Potential Analysis Maps.

19        Maureen Hand (USA), O. H. G., David Infi eld (United Kingdom), Peter H. Jensen (Denmark), Vladimir Nikolaev (Russia), Mark O’Malley (Ireland), Graham Sinden (United Kingdom/Australia), Arthouros Zervos (Greece). Wind Energy.  (2010). 

20        J.K. Kaldellis*, D. A. Life cycle energy and carbon footprint of offshore wind energy Comparison with onshore counterpart.  (2017). 

21        IPCC, I. P. O. C. C. RENEWABLE ENERGY SOURCES AND CLIMATE CHANGE MITIGATION SUMMARY FOR POLICYMAKERS AND TECHNICAL SUMMARY.  (2012). 

22        Thomas Bruckner (Germany), L. F. U., Edgar Hertwich (Austria / Norway), Alan McKinnon (UK / Germany), Daniel Perczyk (Argentina), Joyashree Roy (India), Roberto Schaeffer (Brazil), Steffen Schlömer (Germany), Ralph Sims (New Zealand), Pete Smith (UK), Ryan Wiser (USA). Technology-specific Cost and Performance Parameters.  (2014). 

23        COUNCIL, G. W. E. GLOBAL WIND REPORT 2024.  (2024). 

24        Chen Li, J. M. M., Arnold Tukker, and Bernhard Steubing. Environmental Impacts of Global Offshore Wind Energy Development until 2040.  (2022). 

25        Orsted. What is the carbon footprint of offshore wind?  

26        HaskoningDHV, R. Carbon Footprint Assessment.  (2020). 

27        Berndt*, M. L. Influence of concrete mix design on CO2 emissions for large wind turbine foundations.  (2015). 

28        Alexandra Bonou ⇑, A. L., Stig I. Olsen. Life cycle assessment of onshore and offshore wind energy-from theory to application.  (2016). 

29        Liang Tsai, J. C. K., Brett S. Simon, Rachel M. Chalat, and Gregory A. Keoleian. Life Cycle Assessment of Offshore Wind Farm Siting.  (2016). 

30        Spyroudi, A. Carbon footprint of offshore wind farm components.  (2021). 

31        Shifeng Wang a, c., Sicong Wang b, *, Jinxiang Liu a. Life-cycle green-house gas emissions of onshore and offshore wind turbines.  (2019). 

32        R Camilla Thomson, G. P. H. Life Cycle Costs and Carbon Emissions of Offshore Wind Power.  (2015). 

33        Stephen C.L. Watson a, b., *, Paul J. Somerfield a, Ana¨elle J. Lemasson c, Antony M. Knights c, Andrew Edwards-Jones a,b, Joana Nunes a, Christine Pascoe a, Caroline Louise McNeill a, Michaela Schratzberger d, Murray S.A. Thompson d, Elena Couce d, Claire L. Szostek a,b, Heather Baxter a,b, Nicola J. Beaumont The global impact of offshore wind farms on ecosystem services.  (2024). 

34        Chen Li, J. W. P. C., Laura Scherer, José M. Mogollón, Ulrike Braeckman, Jan Vanaverbeke, Arnold Tukker, and Bernhard Steubing. Offshore Wind Energy and Marine Biodiversity in the NorthSea: Life Cycle Impact Assessment for Benthic Communities.  (2023). 

35        Elizabeth T. Methratta, A. H., Brian R. Hooker, Andrew Lipsky and Jonathan A. Hare. Offshore Wind Development in the Northeast US Shelf Large Marine Ecosystem.  (2020). 

36        Chia-Hsiang Chen 1 and Nan-Jay Su 2, 4. Global Trends and Characteristics of Offshore Wind Farm Research over the Past Three Decades: A Bibliometric Analysis.  (2022). 

37        Fatemeh Rezaei a, Pasquale Contestabile a,b, Diego Vicinanza a,b,c, Arianna Azzellino Towards understanding environmental and cumulative impacts of floating wind farms Lessons learned from the fixed bottom offshore wind farm.  (2023). 

38        Andrew B. Gill, S. D., Andrew Lipsky, Ninon Mavraki, Elizabeth Methratta and Robin Brabant. SETTING THE CONTEXT FOR OFFSHORE WIND DEVELOPMENT EFFECTS ON FISH AND FISHERIES.  (2020). 

39        Van Hoey, G., Bastardie, F., Birchenough, S., De Backer, A., Gill, A., de Koning, S., Hodgson, S., Mangi Chai, S., Steenbergen, J., Termeer, E., van den Burg, S., Hintzen, N.,. Overview of the effects of offshore wind farms on fisheries and aquaculture (2021). 

40        Steven Degraer, D. A. C., Joop W.P. Coolen, Zoë L. Hutchison, Francis Kerckhof, Bob Rumes and Jan Vanaverbeke. OFFSHORE WIND FARM ARTIFICIAL REEFS AFFECT ECOSYSTEM STRUCTURE AND FUNCTIONING.  (2020). 

41        Karl M. Werner a, 1, Holger Haslob a, Anna F. Reichel a, Antje Gimpel a,b, Vanessa Stelzenmüller a. Offshore wind farm foundations as artificial reefs: The devil is in the detail.  (2024). 

42        Lijing Wang 1 , Bangguo Wang 1 , 2 , Wenxi Cen 1 , 2 ,Rui Xu 3 , 4 ,Yuwei Huang 5 , Xin Zhang 1 , 2 , Yinghui Han 1 , 2 , ∗, Yuanxun Zhang 1 , 2 , 6. Ecological impacts of the expansion of offshore wind farms on trophic level species of marine food chain.  (2024). 

43        T. Aran Mooney, M. H. A. a. J. S. ACOUSTIC IMPACTS OF OFFSHORE WIND ENERGY ON FISHERY RESOURCES.  (2020). 

44        Zoë L. Hutchison, D. H. S. a. A. B. G. The Interaction Between Resource Species and Electromagnetic Fields Associated with Electricity Production by Offshore Wind Farms.  (2020). 

45        Aurore Raouxa, b., ∗, Samuele Tecchioa, Jean-Philippe Pezyb, Géraldine Lassallec, Steven Degraerd, Dan Wilhelmssone, Marie Cacherag, Bruno Ernandef, Camille Le Guena, Matilda Haraldssona, Karine Grangeréa, Franc¸ ois Le Loc’hg, Jean-Claude Dauvinb, Nathalie Niquila. Climate change effects on the ecophysiology and ecological functioning of an offshore wind farm artificial hard substrate community.  (2022). 

46        Joshua van Berkel, H. B., Asbjørn Christensen, Lars O. Mortensen, Ole Svenstrup Petersen and Frank Thomsen. The Effects of Offshore Wind Farms on Hydrodynamics and Implications for Fishes.  (2020). 

47        Hall R a, Topham E b,a, Jo˜ao E Environmental Impact Assessment for the decommissioning of offshore wind farms (2015). 

48        Ashley M Fowler1*, A.-M. J., Jon C Svendsen3, Peter I Macreadie4, Daniel OB Jones5, Arjen R Boon6, David J Booth1, Robin Brabant7, Emily Callahan8, Jeremy T Claisse9, Thomas G Dahlgren10,11, Steven Degraer7, Quenton R Dokken12, Andrew B Gill13, David G Johns14, Robert J Leewis15, Han J Lindeboom16,17, Olof Linden18, Roel May19, Albertinka J Murk20, Geir Ottersen21,22, Donna M Schroeder23, Sunil M Shastri24, Jonas Teilmann25, Victoria Todd26,27, Gert Van Hoey28, Jan Vanaverbeke7, and Joop WP Coolen. Environmental benefits of leaving offshore infrastructure in the ocean.  (2018). 

49        Vanessa Spielmann a, Jennifer Dannheim b,c, Thomas Brey a,b,c, Joop W.P. Coolen d,e. Decommissioning of offshore wind farms and its impact on benthic ecology.  (2023). 

50        Aurore Raouxa, b., ∗, Samuele Tecchioa, Jean-Philippe Pezyb, Géraldine Lassallec, Steven Degraerd, Dan Wilhelmssone, Marie Cacherag, Bruno Ernandef, Camille Le Guena, Matilda Haraldssona, Karine Grangeréa, Franc¸ ois Le Loc’hg, Jean-Claude Dauvinb, Nathalie Niquila. Benthic and fish aggregation inside an offshore wind farm: Which effects on the trophic web functioning?  (2017). 

51        WindEurope. Offshore wind and biodiversity.   

52        Roberto Danovaro a, b., *, Silvia Bianchelli a,b, Paola Brambilla c, Gaia Brussa d, Cinzia Corinaldesi b,e, Adriana Del Borghi f, Antonio Dell’Anno a,b, Simonetta Fraschetti b,g, Silvestro Greco h, Mario Grosso d, Ettore Nepote a,b, Lucia Rigamonti d, Ferdinando Boero. Making eco-sustainable floating offshore wind farms: Siting, mitigations, and compensations.  (2024). 

53        Tobias Bo¨ rger *, T. L. H., Melanie C. Austen. Valuation of ecological and amenity impacts of an offshore windfarm as a factor in marine planning.  (2015). 

54        Ian D. Bishopa, David R. Millerb. Visual assessment of off-shore wind turbines the influence of distance, contrast, movement and social variables.  (2016). 

55        John Glasson, B. D., Tokunbo Olorundami and Kellie Welch. Guidance on assessing the socio-economic impacts of offshore wind farms.  (2020). 

56        Alice Freiberg1, C. S. J. H. A. S. The influence of wind turbine visibility on the health of local residents.  (2018). 

57        Innovation, E. Why People Oppose Or Support Offshore Wind: Distilling The Key Factors That Drive Social Acceptance Of Ocean Renewable Energy.  (2022). 

58        Ollson2, L. D. K. a. C. A. Health effects and wind turbines A review of the literature.  (2011). 

59        WorldBank. THE STRATEGIC value of community benefits in offshore wind development.  (2024). 

60        Global Wind Energy, C. Global-Wind-Workforce-Outlook-2024.  (2024). 

61        Fact, W. E. T. The Social Research on Wind Energy Offshore.   

62        WindEurope. Briefing on Offshore wind and fisheries.  (2024). 

63        Dhavle, J. & Nguyen, T. Enabling frameworks for offshore wind scale up: innovations in permitting.  (International Renewable Energy Agency, 2023).

64        United Nations Convention on the Law of the Sea.  (1982). 

65        Salvador, S. & Ribeiro, M. C. Socio‐economic, legal, and political context of offshore renewable energies. WIREs Energy & Environment 12, e462 (2023). https://doi.org:10.1002/wene.462

66        Vasconcelos, R. M. D., Silva, L. L. C., González, M. O. A., Santiso, A. M. & De Melo, D. C. Environmental licensing for offshore wind farms: Guidelines and policy implications for new markets. Energy Policy 171, 113248 (2022). https://doi.org:10.1016/j.enpol.2022.113248

67        Dr. Christian, K. & Dr. Anna Leah Tabios, H. Offshore Wind Worldwide: Regulatory Framework in Selected Countries. 163 (Hogan Lovells, Hamburg, 2023).

68        International Energy, A., Holttinen, H. & Jørgensen, B. H. IEA Wind TCP Annual Report 2023. (2024).

69        Paris Agreement – United Nations Framework Convention on Climate Change (UNFCCC).  (2015). 

70        The North Seas Energy Cooperation (NSEC).  (2016).